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hedwig

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  • Gender
    Female
  • Exams
    May 2012
  1. Thank you very much! That makes sense, I understand it now
  2. b) The energy used (and thus required) is 15kWh (15kW per hour) which equals 15(3.6 x 106J) = 54000kJ per hour. Over 1 day (24 hours) that becomes 1296000kJ (1296MJ) of enegry needed per day. Using the value for the energy we need and the efficiency of the photovoltaic cells (18%), we can find the actual energy needed . 1296 x 106(1/0.18) = 7200 MJ Using the energy gained per square metre per day from part a) (11520 kJ = 11.52MJ), we can find the area needed. Area required = energy needed/enegry per unit area A = 7200000000/11520 = 625000m2 (which, to be completely honest, is ridiculous
  3. A typical family home uses a total of about 15 kWh of electrical energy per day and needs to heart about 45 kg (litres) of water from 12oC to 80oC for showers etc. If a house is in an area where it can receive, on average, about 400 W m-2 of solar radiation for about 8 hours per day calculate: a) The collecting area of the solar water heater if it has an efficiency of 40%; b) The collecting area of the photovoltaic cells if their efficiency is 18%. (1 kWh = 3.6 x 106J) (Note: these calculations do not include energy used to heat the house during the winter.) I'd appreciate it if you could expl
  4. I am having trouble with the denominator's GS. I found the pattern, drew a table of the n against the denominator for each 4 r diagonals. I found 4 quadratic equations each. I then found a GS. I've checked and checked. It seems correct. However, when I replace for E5(2), it does not give the correct answer. I would really appreciate help from someone who found the correct one! Through PM, since writing the equations here are forbidden.. Thank in advance
  5. I'm about 170 cm.. I doubt I'll grow any taller though
  6. I haven't couldn't decide on a topic for my extended essay. I'm currently thinking about various things (I'm most probably going to do a comparison between to literary works) & was wondering... do you think writing about John Green's work would be a bad idea for an extended essay? (Since his books are mainly for young adults.) Thanks!
  7. I started learning English in kindergarten when I was about 5 or 6 years old. Unfortunately, after 4th grade all my English teachers were rubbish so I have my enthusiasm for books to thank regarding my vocabulary and such Also, TV shows and movies helped a lot!
  8. I've no idea what German Ab Initio is but I take SL German
  9. If you fear death, the most rational thing to do would be to know when you're going to die, so that you don't have to worry about that date sneaking up on you. If it's still a long way off, you can have the comfort of knowing that you're not going to die anytime soon. If it is soon, then you know that it's coming up and you can prepare as necessary. I completely agree. If I knew that I would have a rather short life, I would quit worrying about trivial things, and live life to the fullest without worrying about every decision I make & how it would affect my future!
  10. This may sound a bit morbid, and I'm sorry if it does, but I find it interesting. Would you like to know the date of your death? Why or why not?
  11. I always study better when it's dark outside. I generally sing when I'm solving math or physics problems.
  12. Thank you! That helped a lot and includes basically everything I needed cheers
  13. I've been trying unsuccessfully to delete a topic I created. Would greatly appreciate your help. Thanks!
  14. Hi! I'd really appreciate if you could help me out with this question: Discuss one reliability concern for patients undergoing robotic surgery. Our teacher said it must offer a considered and balanced rewiev that includes a range of arguments, factors or hypotheses. Opinions or conclusions should be presented clearly and supported by appropriate evidence. Honestly, I have no idea about this. Any help would be great! Thanks
  15. HL Maths and Physics look fantastic on your diploma, especially if you're considering engineering. & based on the fact that you're taking design technology as well, your determination is quite clear, in my opinion. With the appropriate grades, there is no reason for you not to apply to Oxford and Cambridge.
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